Sildenafil citrate is the active ingredient in the medication commonly known as Viagra. It is a phosphodiesterase type 5 (PDE5) inhibitor used primarily to treat erectile dysfunction (ED) and, under the brand name Revatio, to treat pulmonary arterial hypertension (PAH).
In the treatment of erectile dysfunction, sildenafil citrate works by enhancing the effects of nitric oxide, a natural chemical the body produces that relaxes muscles in the penis. This relaxation increases blood flow to the penile area during sexual stimulation, helping to achieve and maintain an erection. Sildenafil citrate typically begins to work within 30 to 60 minutes after ingestion and its effects can last for about 4 to 5 hours, during which sexual stimulation is necessary to achieve an erection.
For pulmonary arterial hypertension, sildenafil citrate works by relaxing blood vessels in the lungs, which lowers blood pressure and improves exercise capacity in individuals affected by this condition.
Sildenafil citrate is taken orally, and it is available in various dosages, usually prescribed based on the individual's health condition and response to the medication. It's important to use sildenafil citrate under the guidance of a healthcare provider to ensure it is appropriate for the individual’s health status and to avoid potential side effects or interactions with other medications.
Common side effects of sildenafil citrate can include headaches, flushing, indigestion, nasal congestion, dizziness, and visual disturbances. Serious side effects are rare but can include sudden vision loss, hearing loss, or an erection lasting more than four hours, which requires immediate medical attention. Consulting with a healthcare provider before starting sildenafil citrate is crucial to determine if it is safe and suitable for the individual's specific health needs.